This patch backports r228136 from trunk to Google/4_9. The only
difference is that I have added the option disabling to our
Google-specific routine for removing profile options when the
specified profile gcda file is not found.
Passes regression tests. Ok for google/4_9?
Thanks,
Teresa
2015-09-25 Teresa Johnson <tejohn...@google.com>
Google ref b/24265250
* opts.c (finish_options): Unset -freorder-blocks-and-partition
if not using profile.
(set_profile_use_options): Unset -freorder-blocks-and-partition
if input profile not found and it wasn't explicitly set.
Index: opts.c
===================================================================
--- opts.c (revision 228063)
+++ opts.c (working copy)
@@ -787,6 +787,16 @@ finish_options (struct gcc_options *opts, struct g
}
if (opts->x_flag_reorder_blocks_and_partition
+ && !opts_set->x_flag_profile_use)
+ opts->x_flag_reorder_blocks_and_partition = 0;
+
+ /* Disable -freorder-blocks-and-partition when -fprofile-use is not in
+ effect. Function splitting was not actually being performed in that case,
+ as probably_never_executed_bb_p does not distinguish any basic blocks as
+ being cold vs hot when there is no profile data. Leaving it enabled,
+ however, causes the assembly code generator to create (empty) cold
+ sections and labels, leading to unnecessary size overhead. */
+ if (opts->x_flag_reorder_blocks_and_partition
&& !opts_set->x_flag_reorder_functions)
opts->x_flag_reorder_functions = 1;
@@ -1365,6 +1375,8 @@ set_profile_use_options (struct gcc_options *opts,
(PARAM_MAX_INLINE_INSNS_AUTO,
default_param_value (PARAM_MAX_INLINE_INSNS_AUTO),
opts->x_param_values, opts_set->x_param_values);
+ if (!opts_set->x_flag_reorder_blocks_and_partition)
+ opts->x_flag_reorder_blocks_and_partition = false;
}
if (!opts_set->x_flag_branch_probabilities || reset)
--
Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
